So just as an experiment I put the Flirc Case with all 4 threads working on seti@home on top of my WHS homeserver. The case has a few 120mm quite 900rpm fans that exhaust the case heat up and out. So it isn't the coolest air, but just really to increase air movement. Just with doing that the temp went down to around 54~55 degrees.
The flirc case itself provides a great way to pull the heat off the cpu with a good amount of thermal capacity. Once that is done just a bit of air movement in the room around the case will probably be more then enough to meet anyones desires for cooling with that case.
I have been trying to wrap my head around a way t do some kind of forced air down directly on the cpu with a modified top to the case. This really highlights that probably isn't the way to go. Simply a way to push air up and around the case will pull the heat off more evenly. Something like a stand with a 120mm or 80mm fan it would probably be the perfect way to enhance the cooling for the Flirc case. But then that also kind of goes against what it's intended use case is though .

Smblackledge,
I went ahead and opened up seti@home to get all it can from the pi in my flirc case. It does run a bit warmer with all 4 cpu's chuging full speed. but even with that it is hovering around 72 and 73 with an occasional hit at 74 Degree's. Since thermal throttleing starts at a little above 80 this should be really good news from the standpoint of not overheating.
There are a few things about this. I suspect just a little air movement would make a huge difference. The area I have this pi the air is pretty stagnant. This also speaks a ton to the thermal transfer of the case. It is amazing that it can funnel all of this heat into it and with just convection keeping that processor cool enough not to throttle.

I think the question is what do you consider a problem. From simply a heat dissipation standpoint it does a really good job cooling the CPU. Does the case get fairly warm yes, but it does do a great job cooling the Pi4 which is really about just moving the heat from the CPU to something else that can facilitate dissipating the heat. Because of the size of the case it does a really good job of pulling it off the CPU and then getting rid of it.
My FLIRC case is connected to a PI4 that has been running Seti@home for a few days now straight. Before the case i couldn't run one thread for more then a few min before the CPU was thermal throttling. Since installing the case I have had 2 threads running with the CPU going at 1.5ghz the whole time. The system hasn't broken 64 degrees when i have been monitoring it.